Telephone system



HQH. 10E.

TELEPHONE SYSTEM.

APPLlCATluN man MAYI5,1919.

1,881,195, n PGlled June 14,1921;

2 SHEETS-s115171.

H. H. IDE.

TELEPHONE SYSTEM.

APPLxcATmN FILED MAY151919.

Patanted June M9 @EL lamg,

UNITED STATES PATENT OFFICE.

HARRY H. IDE, OF LA GRANGE, ILLINOIS, ASSIGNOR TO KELLOGG SWITCI-IBOARDAND SUPPLY COMPANY, OF CHICAGO, ILLINOIS,

A CORPORATION 0F ILLINOIS.

TELEPHONE SYSTEM.

Application led May 15,

T 0 al? vwhom it may concern Be it known that I, HARRY H. IDE, a citizenot' the United States of America, residing at La (lri'ange, in thecounty of Cook and State of Illinois, have invented certain new anduseful Improvements in Telephone Systems, of which the following is aspeciication.

My invention relates to telephone systems and has to do moreparticularly with systems of the type in which impulses transmitted froma calling substation actuate switches to seek the contacts of the linebeing called. The system which is herein disclosed is particularlyapplicable to private branch exchange systems and is commonly known inthe art as a private automatic exchange, although my invention is in nosense limited to such use. The system'is adapted to serve a plurality ofstations, say twentyive in number, each station of the system beingsupplied with a single motion rotary switch.

A system of the type above described does away with the usual operatorused-in manual private branchlsystems, and an object of my invention isthe provision of an improved circuit arrangement which embodiesdesirable features and advantages all in an efiicient, simple andeconomical manner.

| s The novel features of the invention through the provision of whichthe above' mentioned and other advantageous results are attained will beexplained by reference to the accompanyingdrawings, in which likereference characters in the severalviews denote like parts and in which-Figure 1 is a plan view of a switch adapted to operate in connectionwiththe circuit arrangement;

Fig. 2 is a front elevation of the switch;

Fig. 3 is a right side elevation of the switch;

Fig. 4 is a sectional view of the main shaft showing its constructions,and

Fig. 5 illustrates diagrammatically a system including the circuit of myinvention.

Referring now more particularly to the switch structure illustrated inFigs. 1 to 4, inclusive, the switch comprises a mounting plate 2 towhich are secured the operating parts of the switch and also the bank ofcon- Speccation of Letters Patent.

Patented June 14., 1921. 1919. serial No. 297,244.

tacts B. The switch as illustrated in Figs. L to 4 is similar to thetype of switch illustrated and described in my application, Serial No.271,960, filed January 20, 1919.

The bank contact-s B coperate with the wipers lV, which latter aresupported upon a shaft S. Plate 2 further supports a motor magnet MM, acombined line and interrupter relay LR, a switching relay SW and aringing relay RI.

Contact bank B comprises any suitable number of contact sets, each setincluding a private contact 4, a common Contact 5 and line contacts 6and 7. Twenty-live sets of contacts 4, 5, 6 and 7 per switch is aconvenient number. The contacts are radially disposed between theclamping plates 8 and 9 and are properly spaced and insulated from eachother. Bolts 10 and nuts 11 form the clamping means to secure thecontact bank B, as a whole, between the plates 8 and 9.

To secure the bank of contacts t'o the supporting posts 3 (which aresecurely fastened tio the plate 2), I provide the lower lateI 9 withears 12 and 13 bent over parallelpto the plane of the said plate. Ears12 and 13 and plates 8 and 9 have openings to receive posts 3. The bankB, as a whole, is slipped over the posts threaded engagement with thebridge portion of the ears 12 and 13 are tightened to maintain the bankB, as a. whole, in its adjusted position.

' lVipers 15, 16, 17 and 18, which coperate with the contacts 4, 5, 6and 7 comprise two oppositely extending arms each and the bank ContactB, as a whole, forms a semi-circle so that when one set of wiper armsleaves the last contact set, the other set of wiper arms engagesthe-first contact set. The wipers 15, 16, 17 and 18 are carried by a hub19, which is slipped over the shaft S and when the wipers are adjustedin relation withl the contact banks, a set screw 20 is tightened to holdthe wiper unit 7V upon the shaft S. The wipers l5. 16, 17 and 1S areconductively connected to conducting, rings 21, 22,

23 and 24.` respectively, which a'ire also suitably mounted upon the hub19 but insulated 3, and screws 14 which have screwsurfaces for wiperbrushes 25, 26, 27 and 28, insulatingly mounted upon a stud 29 andclamped yby means of the nut 30, the stud 29, as a whole, being thensecured to the plate 2 by means of the screw 31. The brush wipers 25,26, 27 and 28 contact respectively' and permanently with the conductingrings 21, 22, 23 and 24, and since the rings are as stated conductivelyconnected to wipers 15, 16, 17 and 18, wipers 15, 16, 17 and 18 arealways conductively connected to terminals 26, 27 and 28.

Sleeve 32 supported by plate 2 serves as a bearing forthe shaft S andalso as a bearing for the ratchet 33l which operates to rotate theshaftv S and the wiper unit 1V over the bank contacts. The sleeve 32 hasits one end 32 threaded and its other end provided with a flangedportion 322,- the said ianged portion 322 resting in a recess 34 in theratchet 33. A collar 35 hasscrew-threaded engagement ,with the threadedportion 32 of the sleeve 32 and its peripheral surface also forming abearing for the ratchet 33. The collar 35 is provided with a reducedportion 36 which fits into a suitable orifice 37 inthe plate 2.- Iprovide a nut 38 which has screw-threaded engagement with the threadedportion 32of the sleeve 32 and when the proper adjustment of the ratchet33 and parts is obtained, the nut 38 is tightened to secure the sleeve32 and its supported parts in their Vadjusted position. A plate 39 issecured to the ratchet 33 by means of: the screws 40 and 41, and isprovided with anI angular extension 42 for purposes as' will presentlybe described. The shaft S is provided with a squared portion 43 at itsupper end which enters a square opening 44 in the plate 39. A suitablescrew 45 passing through a suitable opening in the plate 39 hasscrew-threaded engagement with, a suitable tapped orifice in the'squared end 43 of hthe shaft S, thus connecting the shaft S to the plate39 so that when the ratchet 33 is rotated, as will presently bedescribed, the shaft S is also rotated therewith.

The motor magnet MM, which is adapted to move the wipers over bankcontacts, includes a pole piece 46, an armature 47, and a driving paWl48. The eleetromagnet 49 is suitably secured to the pole piece 46 bymeans of a screw 50 which passes through a stud 51, the said screwhaving screw-threaded engagement with ay suitable tapped opening in thecore 52 of the magnet 49.

The pole piece 46 has projecting ears 53 bent at right angles to themain part of the said pole piece, the said ears having suitable tappedorifices which receive screws 54 to fasten the magnet l49, pole piece 46and armature 47 as a unit to the mounting plate 2. 4The pole piece 46 isprovided with projecting ears 55, bent at right angles to the main partof the pole piece, the said ears having suitable openings to receive thepivot pin 56, which plvot pin 56 pivotally suports-the armature 47 ofthe motor magnet M. The armature 47 is also provided with ears 57 whichhave suitable openings to receive the said pivot pin 56. A U-shapedmember 58 is also provided, the arms ot' which also have suitableopenings for receiving the pivot pin 56. T o pivotally support thearmature 47 upon the pole piece 46, the pivot pin 56 is inserted throughthe openings in the ears of the pole piece 46 and the ears 57 of thearmature 47, and through the openings in the arms of the U-shaped member58. One arm of the member 58 fits between one of the supporting ears 55of the pole piece 46 and the adjacent ears 57 of the armature 47. A setscrew 60 is provided and has screw-threaded engagement with the yoke endof the U-shaped member 58. The set screw 60 is used to securely hold thepivot pin 56 in place relative to theheel iron 46 and armature 47.

rllhe armature 47 carries a pivoted driving pawl 48 which is normallyheld against an adjustable stop 62 by means ot a leaf spring 63, thesaid leaf spring 63 being held in place by means of a screw 64. T headjustlable stop 62' is pivotally secured to the mounting plate 2 bymeans of a screw 65. The sto 62 has an enlarged end 62 provided wlth aslot 66, through which a screw 67 passes. To adjust the pawl 48, thescrews and 67 areloosened and thestop 62 is then moved about its pivotscrew 65, causing the angular portion 622 to move to the right or left,as the case may be, and when the proper adjustment is obtained, thescrews 65 and 67 which have screw-threaded engagement with suitabletapped openings in the plate 2, are tightened to hold it in its adjustedposition. The armature 47 is held in its normal position by means of acoil spring 68, thetsaid spring having its one end fastened to a pin 69which is staked to the pole piece 46, and its other end 'is secured toan adjustable screw 70. The screw 70 passes through a suitable openinginthe arm 71, which arm 71 is integrally formed with the armature 47, thelsaid screw 70 being provided with an adjustable nut 72. The tension ofthe `spring 68 is regulated by means of the nut 72. A set of contactsprin J is associated with the motor magnet. M, the said springs beinginsulatingly mounted upon the pole piece 46 by meansof the screws 73,which are suitably insulated from the springs J.

The pawl 48 is adapted to engage a tooth of the ratchet Wheel 33 u oneach actuation of the motor magnet. Ml and an adjustable stop post 74 isprovided to limit the stroke of the pawl 48 so that the wipers 15.

16, 17 and 18 are only advanced one step at a time. The stop post 74 hasa reduced pormames tion which passes through a suitable slot in theplate 2. The stop 74 may be moved forward or backward as the case maybe, and when the desired adjustment is obtained suitable means aretightened to securely hold the stop 74 in its adjusted position.

The line relay LR, ringing relay RI and the switching relay SW aresuitably mounted upon a bracket 76, which bracket .is in turn secured tothe mounting plate 2 by mean-s of the screws '77. The relays LR, RI andSvV are similarly constructed and comprise the usual electromagnet 78,heel iron 79 and pivoted armature 180. Nuts 181, having screw-threadedengagement with threaded portionsof the core of the electromagnets,secure them to the bracket 76.

A set of oil-normal contacts ON are insulatingly mounted upon a bracket182 by means of the screws 183, and are held in their normal position bymeans of the angular extension arm 42 of the plate 39 in the form ot' anarm 42. The arm i2 when the switch is at normal engages a rubber butter283 to hold the said oit-normal contacts ON in their normal position.Upon the first step of the switch Wipers oli normal, the arm 42disengages the butter 283 allowing the contacts ON to assume theiralternate position and remain in such position until the arm 42 againengages the buti'er 283` which occurs when the switch has completed arevolution. The bracket 182 is suitably secured to the mounting plate 2by means of the screws 184. A condenser K is mounted upon the plate 2 bymeans of a bracket 185 secured to the plate 2 by means of the screw 186.

The circuit in Fig. 5 shows a calling substation A connected to theswitch circuit D of my invention and adapted t0 operate with the switchstructure just described. The calling substation A comprises the usualsubstation apparatus and in addition comprises a calling device CD and agrounding or ringing key GK for purposes as will presently be described,and the called line C is similarly equipped.

Assuming now that the subscriber at the calling substation A initiates acall, he removes his receiver, thus closing a circuit lfor the linerelay LR and ringing relay RI, traced from battery through the windingot relay LR, conductor 80, through the substation, conductor 81 toground through the winding of ringing relay RI. rlhe two relays LR andRI are thus energized in series. Assuming further that it is thesubscriber at substation C that is wanted and his number is 15. thesubscriber at substation now actuates his calling device to send tifteenimpulses of current over the line by first sending ten impulses and thenfive, as is well understood, or any other combination of impulses tomake the requisite number.

`contacts 4, 6 and 7,

construction. Upon the first denergization of relay LR, an energizingcircuit for motor magnet MM is established, traced from batt'ery,through the Winding of motor magnet MM, conductor 82, normal Contact 83of relay LR, conductor 84, normal contact 85 of switching relay SW,conductor 86, to ground at alternate contact 87 of ringing relay RI. Themagnet MM upon energization causes the pawl 48 to engage a tooth of theratchet 33, stepping the wipers 15, 17 and 18 into engagement with thefirst set of and the motor magnet MM is energized and denergized fifteentimes due to the closing and opening of normal contact 83, and thewipers 15, 17 and 18 are stepped into engagement with the fifteenth setof contacts 4, 6 and '7 which are the contacts of the called substationC. Upon the first step of the wipers oil" normal, off-normal contacts ONassume their alternate positions and the closing of alternate contact 88places a ground or busy potential upon the private normals 89 of thecalling substation A, making it busy against any incoming calls.

After the subscriber at the calling substation A has sent the impulses,he depresses the key GK to impress ringing current upon the calledsubscribers line, and relay LR re mains energized while relay Rl isshort circuited and falls back. Assuming that the called line is idle,the depression of the key GK brings about a series energizing circuitforthe switch relay SW and the switch relay SW of the individual switch Dof the called line C, traced from battery through the lower winding ofrelay Si' l. conductor 90, normal contact 91 of primary off-normalcontacts 0N', conductor 92, normal contact 93 of relay 14R/conductor 94.normal contact 95 of relay R1, conductor 96, Contact 1, wiper 15,conductor v97, upper winding of relay SW, conductor 98, alternatecontact 99 of relay LR, normal contact 10() of relay RI (the said relayRI restoring when the key GK is depressed as it is shunted, the saidshunt being traced from 0fround at alternate contact of the key Gconductor 81 to ground through the winding of relay RI), conductor 101,conductor 102, to ground at alternate contact 88 of primary off-normalcont-acts ON. The closing of alternate contact 111 of switching relay SWcloses a locking circuit for itself, traced from battery, through thelower winding of relay SW, alternate contact 111, conductor 86, toground at alternate contact 87 of relav Rl. U on each actuation of thekey GK. relay R restores for reasons as: aircady delill) scribed, andthe opening of alternate contact 8T opens the circuit of relay SW, butan alternative circuit for relay SlV is closed during the denergizationof relay RI, traced from battery` through the lower winding of relayFill?, alternate contact 111, conductortiti, conductor 10i-l, alternatecontact 101 of relay LR, conductors 105 and 102 to ground at alternatecontact S8 of ottu normal contacts ON. Each depression of the key GKimpresses ringing current upon the called line. due to the denergizationof relay Rl upon each actuation of key GK, the ringing circuit beingtraced from the ungrounded pole of the generator G, alternate contact10G of relay Sill', conductor 10T. normal contact 130 ot relay Rl,alternate contact 109 of relay SlV. wiper 18, conductor T. through thecall bell and condenser of the called substation back through contact 6,wiper 1T. alternate contact 110 of relay Sll'. conductor 81, throughrelay RI to ground. The closing of alternate contact 112 of relay Sli'places a ground or busy potential upon the private contact 4 from groundat alternate contact H8 of off-normal contacts ON, cmiductors 102 aud105, alternate contact 104 of relay LR. conductors 103 and 8G, alternatecontact 112 of relay SlV, conductor 9T. wiper 15 to contact 4, thuspreventing any other calling subscriber from engaging with the contactsof the called line.

lVhen the called subscriber at the substation C answers in response tohis call bell, the removalof the receiver thereat closes an energizingcircuit for the line relay LR and the ringing relay RI of the switch Dassociated with `the called line, from battery, through the Winding ofrelay LR', conductor 113. through the now closed contacts of thesubst-ation switch hook, conductor 11-ito ground through the winding ofrelay RI'. The closing of alternate'contact 115 of relay RI closes alocking circuit for the switching relay Sl l' from battery throughl itsalternate contact 116, conductor 117 to ground at alternate contact 115of relay RI. The subscribers at substations A and ,C are now inconversational circuit, and the'talking circuit may be traced over theheavily marked conductors, the said conductors having the condensers Kand K interposed.

Assuming now that the subscribers at substations A. and C have finishedconversation, the calling subscriber A replacing his receiver upon theswitch hook allows the relays R and LR to restore, due to the opening ofthe switch hook contacts, and the opening of contact. 8T of relay RIopens the locking circuit of switching relay SW', which relay restoresto normal. The closing of normal contact 99 of relay LR and normalcontact 100 of relay RI establishes an energizing circuit formotormagnet MM,

traced from battery, through the winding of magnet MM, its normalcontact 120, conductor 121, alternate contact 122 of olf-normal contactsON, conductor 123, normal contacts 99 and 100, conductors 101 and 102 toground at alternate contact 88 of ott-normal contacts ON. The magnet MM4upon energization causes the Wipers 15, 17 and 18 to be stepped from thecontacts it was engaging and the opening of its contact 120 opens thecircuit of the magnet MM, allowing it to restore, and the closing of itscontact 120 again energizes the magnet MM. The magnet MM is thusenergized and deenergized, stepping the wipers 15, 17 and 18 until thearm 42 again engages the off-normal contacts ON, moving them back totheir normal position, and the opening of contacts`88 and 122 of thesaid off-normal .contacts ON opens the energizing circuit of .magnet MMpreventing further movement of the switch wipers 15, 17 and '18. Thereplacing of the receiver at the called substation C {opens theenergizing circuit for relay RI and LR at the switch hook contacts, andrelay RI restoring opens its alternate contact 115, allowing-theswitching relay SlV to restore provided the calling subscriber hasalready hung u a, which places the apparatus of the switch associatedwith the called subscriber,'at normal. The apparatus used inestablishing the above described connection is now at normal and isavailable for use in establishing other connections.

Assuming now that the called lineis busy, the operation/of 'the circuitis the same'as previously described-up to the timeI that the callingsubscriber depresses lthe key- GK. It the wanted line is busy as acalling line, its private normals 4 will be grounded from the alternatecontact 126 ofthe oit-normal contacts ON', while if busy, as a calledline, its private normals will be roundedI from the ground extendingthroug the alternate contact of the switching relay STV of the switch ofthe calling line, as already described. The calling subscriber havingselected .the contacts of the called line, now Adepresses the key GK. A.path extends from ground at the busy contact l, wiper 15 of s\vitchD,conductor 97, through the upper Winding of relay SW, conductor 98,alternate contact 99 of relay LR, normal contact 100 of relay RI, (thesaid relay being short circuited upon the depression of the key GK, asalready described), conductors 101 and 102 to ground at alternatecontact 88 of off-normal contacts ON. Relay SlV does not energize-inthis instance, due to its upper winding being grounded at both ends, anda busy signal is transmitted to the calling subscriber, traced from thebusy signal. BB, normal Contact 109 of re lay SW, alternate contact 130of relay RI (the said rela RI again energizing as soon as the key (ih isreleased), through the receiver of the calling subscriber at substationA, back over conductor 81 and through the winding of' relay RI toground. The calling subscriber receiving the busy signal, now replaceshis receiver and this act opens the circuit for relays RI and LR,bringing about the energization of the motor magnet MM, which magnet MMsteps the wipers ahead as previously described, until they reach normal,when the switch is again available for establishing other connections.

lu describing my invention I have employed preferred circuitarrangements, but it is to bc understood that various changes mayreadily suggest themselves to those lskilled in the art, and I,therefore, do not desire to be limited to the exact arrangement shownand described, but aim to cover all such changes and modifications whichcome within the spirit and scope of the appended claims.'

lVhat I claim as new and desire to secure by United States LettersPatent, is:

l. A telephone system including a subscribers line, an automat-icadding-type connector switch individual to said subscribers linecontrolled over the two sides of the subscribers line in series, asingle row or level of bank contacts for said automatic switch, othersubscribers lines terminating in said bank contacts,subscribercontrolled means for said switch for connecting said firstsubscribers line to any one of said other subscribers lines,subscriber-controlled means for ringing the called substation, andautomatic means for moving said switch to normal position.

2. A telephone system including a subscribers telephone line, anautomatic adding-type connector switch individual thereto and controlledover the two sides of the subscribers line in series, bank contacts forsaid switch, subscribers lines terminating in said bank contacts,step-by-ste means for said switch for connectin said rst sub-. scribersline to any of said ot er subscribers lines,'subscriber-controlled'means for rin ing the called substation, and automatic means foroperating said step-by-step means to move the wipers of said switch to anormal position.

3. A telephone system including a subscribers telephone line, anautomat1c switch individual thereto, a pair of-line relays for saidswitch connected to said subscribers line, a Isingle level of bankcontacts for said switch, other subscribers lines connected to said bankcontacts, an impulse sending device for operating one only of said linerelays to cause a connection to be 'established between said firstsubscribers line and one of said other subscribers lines, andsubscriber-controlled means for maintaining said line relay energizedand Jfor denergizing the said other line relay to signal the calledsubscriber.

4. A telephone system includin a subscribers telephone line. anautomatic switch individual thereto, a. pair of line relays for saidswitch connected to said subscribers line, a single level of bankcontacts for said switch, other subscribers lines connected to said bankcontacts, an impulse sending device for operating one of said linerelays to cause a connection to be established between said firstsubscribers line and one of said other subscribers lines,subscriber-controlled means for maintaining said line relay energizedand for denergizing the said other line relay to signal the calledsubscriber, and subscriber-controlled means for denergizing both of saidline relays, whereby said switch resumes a normal position.

5. A telephone system including a subscribers telephone line, anautomatic switch individual thereto, a pair ot' line relays for saidswitch lconnected to said subscribers line, a single level of bankcontacts for said switch, other subscribers lines connected to said.bank contacts, an impulse sending device for operating one of said linerelay-s to cause a connection to be established between said *firstsubscribers line and one of said other subscribers lines,subscriber-controlled means for maintaining said line relay ener-- gizedand for denergizing the said other line relay to signal the calledsubscriber, and automatic means for said switch, controllable by thedenergization of Aboth the said line relays for advancing the wipers ofsaid switchvto normal position.

6. A connector circuit including a telephone line, a pair ofelectro-magnets in series therewith; means for vibrating the first bydigit impulses, while the second maintains its armature in operatedposition; circuit connections for holding the first in opera-tedposition while the second retracts itsarmature; a test relay switchedinto circuit by said magnets; a source of ringing current connected inwhen said relay is in oneoperative position; a source'of busy currentconnected in when said relay 1s in another operative condition.

7. A connector circuit including a telephone line, a pair ofelectro-magnets in series therewith; means for vibrating the first bydigit impulses, while the second maintains its armature in operatedposition; circuit connections for holding the first-in operatedposition'while the second retracts its armature; a test relay switchedinto circuit by said magnets; a called line; a test relay for said linein circuit with said first relay; a source of current connected to saidcircuit and energizing both said relays when the called lineis idle.

8. A calling and a called telephone line;

a connector for each line, said connectors having each a test relay intemporary circuit with each other; and calling line means for connectinga current source to said circuit. Y

9. A connector having a quick and a slow electroinagnet, the firstretracting and the other holding its armature responsive to substationcontrol; substation means to reverse said positions of said armatures;travel controlling mea-ns sensitive to the first armature relation; andtest controlling means sensitive to the second armature relation.

10. A telephone system including a calling and a called line, eachhaving a connector, said connectors temporarily switched together; atest relay foreach connector adapted to operate in circuit with 'oneanother when the called line is idle; and an ofi' normal contact of eachconnector controlling a circuit of its relay.

11; A telephone system including a call ing and a called line, eachhaving a conncctor, said connectors temporarily switched together; atest relay f'or each connector adapted to operate in 4circuit with oneanother when the called line is idle; and two ofi" normal contacts ofeach connector controlling the circuit of its relay.

12 A telephone system including telephone lines; a connector, an offnormal contact serving to place a busy potential on the private normalof said connector; means lfor connecting said contact to a wiper ofysaid connector to test the called line; a test relay with a winding inseries between said contact and said wiper, and operating in a mannerdependent on the electrical condition of an engaged called line contactfor switching a connection t0 said wiper to render the called linebusy.V

13. A connector 'for automatic exchanges including a relay adapted to beoperated in series with the two limbs of a line or over one limbthereof; a called line; and a test relay for said connector to test thecalled line having a test winding controlled by said first relay and alocking Winding for said test relay. l

14. A connector for automatic exchanges including a relay adapted to beoperated over the two limbs of the line or over one limb at the will ofthe subscriber; atest relay for said connector, circuit means con-`trolled by said first relay for controlling said test relay; and an offnormal contact in the circuit of said test relay.

15. A connector for automatic exchanges including a relay adaptedto beoperated over the two limbs of the line or over one limb at the will ofthe subscriber; a test relay for said connector, circuit meanscontrolled by said first relayl for controlling said test relay; and twooff normal contacts for said connector and a circuit'connection fromeach contact to Said test relay.

16. A connector for automatic exchanges including a relay adapted to -beoperated over the two limbs of the line or over one limb at the will ofthesubscriber; a test relay for said connector, circuit means.controlled by said first relay for controlling said test relay; meansfor switching said test relay tooperatively connect with the calledline, an off normal contact controlled from the callin line, anotherycontrolled from the calledlmc, the circuits of said test relay being`connected to both said contacts.

1T. A connector for automatic exchanges including a relay adapted to beoperated over the two limbs of the line or over one limb at the will ofthe subscriber; a test relay for said' connector, circuit meanscontrolled by said first relay for controlling said test relay; meansfor switching said test relay` to connect with thel called line, an ofi'normal contact controlled from the calling line, another controlled fromthe called line, the

circuits of said test relay being connected to both said contacts; and atalking circuit of said connector including normally open contacts ofsaid test relay.

18. A connector for automatic exchanges including a relay adapted to beoperated over the two limbs of the line or over one limb at the will ofthe subscriber; a test relay for said connector, circuit meanscontrolled by said first relay for controlling said test relay; an ofi'normal contact in the circuit or said test relay; and ringing and busyback connections controlled by said test relay. f

19. A connector for automatic exchanges including a relay adapted to beloperated over the two limbs of the lineor overdone limb at the will ofthe subscriber.; a test relay `for said connector, circuit meanscontrolled by said first relay for controlling said test relay; an ofi"normal contact in the circuit ot said test relay; a talking circuit ofsaid connector including normally open contacts of said test relay;ringing and busy back connections controlled by said test relays.

20. Al connector for automatic exchanges including a relay adapted to beoperated over the two limbs of the line or over one limb at the will ofthe subscriber; atest relay for said connector, circuit means controlledby said first relay for controlling said test relay; a slow releaserelay for said connector subject to substation control, said test relaywhen energizing lookin irst over a contact of said first mentionerelayand then over a Contact of said`slow relay.

21. A connector for automatic exchanges including a relay Iadapted to beoperated over the two limbs of the line or over one limb at the will ofthe subscriber; a test relay for said connector, circuit meanscontrolled by said first relay for controlling said test relay; a slowrelay for said connector subject to substation control, said slow relayalso controlling said test relay; a called line and a relay therefor,means for energizing said test relay and said called line relay inseries, said relays locking over a contact of said first mentioned relayand also over an independent locking circuit including a contact of saidslow relay.

22. A connector t'or automatic exchanges, including a test relay. a slowrelay subject to substation control and serving to operatively connectsaid test relay. a third relay, a locking circuit for said test relay.including a switch contact lot' said third relay, another lockingcircuit for Said test relay including a contact of said slow relay andmeans for successively closing said locking circuits.

E23. A connector including a test relay, an energizing circuit and twoholding circuits for said relay. 'and switch means for closing saidthree circuits in succession.

2l. A connector including a relay, line switching contacts on Saidrelay, an energizing circuit and a locking circuit for said relay. andholding means to retain said relay in operated position after theestablishment of said energizing circuit and until said locking circuitis completed.

25. An automatic telephone system including a pair ot' telephone linesconnected to connectors respectively. said lines temporarily switchedtogether, a test relay for each connector, and means for energizing bothsaid test relays when the called line is tested.

26. An automatic telephone system including a pair ot' telephone linesprovided with individual adding-type connectors, respectively. saidlines being temporarily switched together, a relay t'or each connector,and means for energizing both ot' said relays when a connection iseffected.

Signed by me at Chicago, county of Cook and State of Illinois, this 13thday 0f May. 1919.

HARRY H. IDE.

